JPS6134733B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a foamed urethane composite having excellent heat aging resistance and weather resistance. Interior parts of automobiles, aircraft, etc., such as crash pads, armrests, etc., are made of foamed urethane composites that are coated with soft and semi-hard thermoplastic resin sheets in terms of safety and feel for the human body. In particular, foamed urethane composites such as crush pads, which are exposed to direct sunlight and used in high-temperature environments, often suffer from problems due to heat aging such as hardening and cracking of the coating material. , which is unfavorable not only in terms of feel but also in terms of appearance. The present inventors have arrived at the present invention as a result of intensive research into a foamed urethane composite exhibiting excellent heat aging resistance and weather resistance that overcomes these drawbacks from the viewpoint of treatment technology for coating materials. That is, the present invention provides a foamed urethane composite consisting of a coating material and urethane, in which a surface of the coating material in contact with the foamed urethane resin is selected from the group consisting of a flexible urethane resin, a flexible urethane resin manufacturing raw material, and a vinyl chloride resin. After coating (A) an organic solvent solution or aqueous emulsion containing one or more types of and (B-2) one or more selected from the group consisting of blocked isocyanate compounds, polyN-alkoxymethylmelamine compounds, polyepoxy compounds, polyoxazoline compounds, polydihydroxazine compounds, and reactive polyamide compounds. (B) A foamed urethane composite with excellent heat aging resistance and weather resistance, which is coated with an organic solvent solution and crosslinked by heating. In the present invention, first, the surface of the covering material in contact with the urethane foam contains one or more selected from the group consisting of a flexible urethane resin, a flexible urethane resin manufacturing raw material, and a vinyl chloride resin (A). An organic solvent solution or aqueous emulsion (hereinafter referred to as liquid A) is applied. Thereafter, (B-1) a copolymer consisting of an ethylenically unsaturated monomer having a carboxyl group and an acrylic acid ester and/or a methacrylic acid ester, and (B-2) a blocked isocyanate compound are further applied on the surface coated with Liquid A. , a polyN-alkoxymethylmelamine compound, a polyepoxy compound, a polyoxazoline compound, a polydihydroxazine compound, and a reactive polyamide compound (B) an organic solvent solution (hereinafter referred to as B solution) ) is coated and cross-linked by heating. Solution B contains the above (B-1) copolymer and (B
-2) Compound is an essential component, and with (B-1) copolymer alone, it is difficult to control the strength and solvent resistance of the coating film even when used in combination with Part A, and the effect of improving heat aging resistance is Hard to admit. If the compound (B-2) is used alone, the self or the liquid A component will be applied to the crosslinking target, and the effect of improving heat aging resistance and weather resistance cannot be sufficiently exerted. That is, in solution B, the (B-1) copolymer is the main agent, and the (B-2) compound is an auxiliary agent that brings crosslinking to the (B-1) copolymer. In addition, in the present invention, it is necessary to further apply solution B after applying solution A to the surface of the coating material in contact with the urethane, and the effect of improving the heat aging resistance of the coating material and composite material is small if only solution A is applied. By further applying Solution B, it exhibits significantly superior heat aging resistance and weather resistance. On the other hand, if only solution B is applied, the adhesion between the coating material and the coating film is poor, and after urethane injection and foaming, the coating material and the foamed urethane layer become separated, which is not preferred in practice. Furthermore, if Solution A is applied after Solution B is applied, an excellent composite cannot be obtained. Next, each component of the present invention will be described. A
The "flexible urethane resin" that is comprised of the liquid refers to active hydrogen compounds having two or more active hydrogen groups such as hydroxyl groups, carboxyl groups, and amino groups, diisocyanates, adducts of diisocyanates, low polymers of diisocyanates, and urethane. It can be produced by reacting isocyanates such as prepolymers and blocked isocyanates. "Flexible urethane resin manufacturing raw material" refers to a raw material containing the above-mentioned active hydrogen compound and isocyanate, which is converted into a flexible urethane resin by heating or using a catalyst in the composition or after being applied. . The active hydrogen compounds include water, ethylene glycol, propylene glycol, polyoxyalkylene polyol, polytetramethylene ether glycol, condensed polyester, lactone polyester, acrylic polyol, castor oil,
Examples include hydroxyl-terminated polybutadiene oligomers. Isocyanates include aromatic diisocyanates such as 4,4'-diphenylmethane diisocyanate, tolylene diisocyanate, and xylylene diisocyanate, aliphatic diisocyanates such as hexamethylene diisocyanate, adducts of the above diisocyanates, and low polymer preforms. Examples include polymers and blocked isocyanates. "Vinyl chloride resin" includes polyvinyl chloride, copolymers mainly composed of vinyl chloride,
For example, vinyl acetate-vinyl chloride copolymer, ethylene-vinyl acetate-vinyl chloride copolymer, acrylic acid ester-vinyl chloride copolymer, propylene-
Examples include vinyl chloride copolymers. It may also be a mixture thereof. The A solution containing one or more resins selected from the above resin group is a solution or an aqueous emulsion in an organic solvent. The organic solvent used to form the organic solvent solution is not particularly limited, but generally includes benzene, toluene, xylene, cymene, kyumene,
Aromatic hydrocarbons such as diethylbenzene, ethylbenzene, and diurene; ketones such as methyl ethyl ketone, methyl isobutyl ketone, acetone, and cyclohexanone; esters such as ethyl acetate and butyl acetate; ethers such as tetrahydrofuran, dioxane, and diethyl ether; dimethyl formamide , amide compounds such as dimethylacetamide,
Examples include nitro compounds such as nitrobenzene and nitrotoluene. The amount of the liquid A to be applied is not particularly limited, but is preferably 4 to 20 g (solid content)/1 m ² . (B-1) The "ethylenic unsaturated monomer having a carboxyl group" constituting the copolymer includes:
Examples include acrylic acid, methacrylic acid, itaconic acid, fumaric acid, maleic acid, maleic acid half ester, and crotonic acid. Furthermore, examples of "acrylic ester and/or methacrylic ester" include methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, n-propyl acrylate, n-butyl acrylate, n-hexyl acrylate, n-octyl acrylate, 2- acrylate
Ethylhexyl, chloromethyl acrylate, chloroethyl acrylate, 2-hydroxyethyl acrylate, ethylene diacrylate, methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, n- methacrylate Examples include hexyl, n-octyl methacrylate, chloromethyl methacrylate, chloroethyl methacrylate, and glycidyl methacrylate. The composition ratio of the ethylenically unsaturated monomer having a carboxyl group and the acrylic ester and/or methacrylic ester constituting (B-1) is not particularly limited, but the ethylenically unsaturated monomer having a carboxyl group The monomer content is 10-90% by weight, preferably 20-80% by weight. In addition, in the copolymer (B-1), other copolymerizable monomers can be used as a copolymer component in an amount of 20 mol % or less, if necessary. Other copolymerizable monomers include acrylamide, metrolated acrylamide, methacrylamide, methylolated methacrylamide, acrylonitrile, methacrylonitrile, styrene, vinyl chloride, vinyl acetate, butadiene,
Examples include isoprene. There is no particular restriction on the molecular weight of the copolymer (B-1), but the intrinsic viscosity is 0.02 to 10 dl/g, preferably
It is 0.1 to 2 dl/g. "(B-2) Blocked isocyanate compounds" include toluene diisocyanate, diisocyanate diphenylmethane, etc. blocked with phenol, caprolactam, malonic acid diester, hydrogen cyanide, diphenylamine, succinimide, acetoacetate, etc. Examples include isocyanate compounds and prepolymers obtained from them and polyols and polyamines. "Poly N-alkoxymethyl melamine compound"
Examples include hexamethylol melamine hexamethyl ether, pentamethylol melamine trimethyl ether, tetramethylol melamine tetramethyl ether, trimethylol melamine dimethyl ether, hexamethylol melamine hexaethyl ether, hexamethylol melamine hexabutyl ether, and the like. Examples of the "polyepoxy compound" include bisphenol A diglycidyl ether, diglycidyl ether, butadiene dioxide, bisphenol A epichlorohydrin, and epoxy prepolymers which are reactants of these and various polyols. “Polyoxazoline compounds” include 2,
2'-tetramethylene (4,4'-dimethyl-2-oxazoline), 2,2'-hexamethylene (4,
4'-dimethyl-2-oxazoline), 2,2'-phenylene (4,4-dimethyl-2-oxazoline), and the like. "Polydihydroxazine compound" includes 5,6-dihydro-4H-1,3-oxazine,
1,3 and 1,4-bis(5',6'-dihydro-
4′H-1′,3′-oxazin-2′-yl)benzene, 1,3 and 1,4-bis(5′,5′-dimethyl-5′,6′-dihydro-4′H-1) ',3'-oxazin-2'-yl)-benzene, 1,3 and 1-,4
-Bis-(6′-methyl-5′,5′-dihydro-4′H
-1',3'-oxazin-2'-yl)-benzene, etc. The "reactive polyamide compound" is a compound in which the hydrogen of the amide group of nylon is substituted with another substituent, such as a methylolated or alkoxylated compound, such as N-alkoxymethyl nylon. As (B-2), a mixture of a polyepoxy compound and a reactive polyamide is particularly preferred. The organic solvent used to make the (B-1) copolymer and the (B-2) compound into an organic solvent solution (B solution) is not particularly limited, and the organic solvent used in the A solution can be Can be used. Further, the organic solvent may be the same as the organic solvent used for liquid A, or may be of a different type. The mixing ratio of the copolymer (B-1) and the compound (B-2) is not particularly limited, but is preferably in the range of 1:1 to 1:0.1 in terms of solid content. In addition, in order to increase the flexibility of the coating film with solution B, ethylene glycol, propylene glycol, diethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, glycerin, trimethylolethane,
trimethylolpropane, hexanetriol,
A polyol compound such as polyvinyl alcohol, a phosphorus plasticizer and/or a polyester plasticizer may be added. The amount of B solution applied is not particularly limited, but is preferably 3 to 7 g {(B-1) and (B-
2) Total weight}solid content/ ^1m2 . Methods for applying Solution A and Solution B to the surface of the coating material in contact with the urethane include a coating method using a roll coater, gravure coater, or knife coater, and a spray coating method using an air gun or airless gun. It may be a method. After application, dry at room temperature, but if possible, dry at 100°C for about 1 minute after applying solution A, and at 100°C after applying solution B.
C. to 120.degree. C. for about 2 minutes is practically preferable. In the present invention, it is sufficient that a coating film of solutions A and B is formed on the surface of the coating material in contact with urethane before urethane injection and foaming, and solutions A and B are applied after vacuum forming the thermoplastic sheet. Either method may be used, such as applying only liquid A to the thermoplastic sheet, applying solution B after vacuum forming, or applying liquid A and solution B to the thermoplastic sheet, followed by vacuum forming. Injection foaming of urethane may be carried out by a conventional method and is not limited in any way. EXAMPLES The present invention will be specifically explained below with reference to Examples, but the present invention is not limited to these Examples. Example (A) Flexible urethane resin, (B-1) A copolymer consisting of an ethylenically unsaturated monomer having a carboxyl group and an acrylic ester or a methacrylic ester, and (B-2) a compound, respectively. The compositions were used in the proportions shown in Table 1, and after being applied to the surface of a calendar-molded soft sheet containing ABS resin, so-called crush pad sheet, in contact with urethane, a weather resistance test was conducted. Further, after coating, urethane was injected and foamed to create a foamed urethane composite, and a heat aging test was conducted. The results are shown in Tables 2 and 3.

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Claims (1)

[Claims] 1. In a foamed urethane composite consisting of a coating material and urethane, one or more types selected from the group consisting of flexible urethane resin, flexible urethane resin manufacturing raw material, and vinyl chloride resin on the surface of the coating material in contact with foamed urethane resin. After coating (A) an organic solvent solution or aqueous emulsion containing (A), (B-1) a copolymer consisting of an ethylenically unsaturated monomer having a carboxyl group and an acrylic ester and/or a methacrylic ester and (B- 2) 1 selected from the group consisting of blocked isocyanate compounds, polyN-alkoxymethylmelamine compounds, polyepoxy compounds, polyoxysazoline compounds, polydihydroxazine compounds, and reactive polyamide compounds
A foamed urethane composite having excellent heat aging resistance and weather resistance, which is characterized by applying (B) an organic solvent solution containing at least one species of organic solvent and crosslinking it by heating.